During normal drilling operations an air/water mixture stream is delivered to a drill bit through hollow drill pipes and other components, the mixture being fed via a porting arrangement incorporated into the attached drill bit. The air/water mixture stream clears drilled earth (known as the chip), provides cooling to the bearings in the drill bit, and reduces air borne dust as the chip leaves the hole during drilling operations.
One disadvantage to the process is that the air/water fluid dramatically reduces bearing life and therefore bit life. It is also noteworthy that mine sites often use recycled water that commonly contains corrosive minerals amplifying the detrimental effect of the water.
The present invention seeks to ameliorate one or more of the above-mentioned disadvantages.